Bonded electronic control unit

Abstract

An apparatus includes a housing, a circuit board, a sealant and a baseplate. The housing may have a shelf and a flange along an open side. The circuit board may be (i) disposed on the shelf of the housing and inside the flange of the housing and (ii) secured to the housing. The sealant may be dispensed (i) through the open side of the housing and (ii) along a gap between the flange and the circuit board. The baseplate may be compressed to the housing thereby causing the sealant to flow between (i) the baseplate and the circuit board and (ii) the baseplate and the flange.

The invention claimed is: 
     
       1. An apparatus comprising:
 a housing having a shelf and a flange along an open side; 
 a circuit board (i) disposed on said shelf of said housing and inside said flange of said housing and (ii) secured to said housing; 
 a continuous bead of sealant dispensed (i) through said open side of said housing and (ii) along a gap between said flange and said circuit board around a perimeter of said circuit board; and 
 a baseplate compressed against said open side of said housing thereby causing said continuous bead of sealant to flow between (i) said baseplate, (ii) said circuit board, and (iii) said flange. 
 
     
     
       2. The apparatus according to  claim 1 , wherein said sealant is cured to bond said circuit board, said housing and said baseplate together as an electronic control unit. 
     
     
       3. The apparatus according to  claim 1 , further comprising a connector and a plurality of compliant pins having a right angle bend assembled to said circuit board, wherein said connector fits into a connector opening in a side of said housing orthogonal to said open side. 
     
     
       4. The apparatus according to  claim 3 , wherein an interface between said connector and said connector opening in said side of said housing is free of said sealant. 
     
     
       5. The apparatus according to  claim 3 , wherein said connector is welded to said housing. 
     
     
       6. The apparatus according to  claim 3 , further comprising a weld ring overlapping an interface between said connector and said connector opening in said side of said housing, wherein said weld ring is welded to a housing weld rib of said housing and a connector weld rib of said connector, and seals said interface between said connector and said housing. 
     
     
       7. The apparatus according to  claim 1 , wherein said housing is secured to said baseplate solely by said sealant. 
     
     
       8. The apparatus according to  claim 1 , further comprising one or more fasteners configured to secure said housing to said baseplate outside of said sealant. 
     
     
       9. The apparatus according to  claim 1 , wherein said baseplate is aligned to said open side of said housing with said sealant already applied prior to said compression of said baseplate to said housing. 
     
     
       10. The apparatus according to  claim 1 , wherein said sealant is cured by at least one of heat curing, humidity curing, ultra-violet light curing, and chemical curing. 
     
     
       11. The apparatus according to  claim 10 , wherein said sealant provides a seal against fluid penetration into an interior of said housing. 
     
     
       12. A method for assembling an electronic control unit, comprising the steps of:
 securing a circuit board to a housing, wherein (i) said housing has a shelf and a flange along an open side and (ii) said circuit board is disposed on said shelf and inside said flange; 
 dispensing a continuous bead of sealant (i) through said open side of said housing and (ii) along a gap between said flange and said circuit board around a perimeter of said circuit board; and 
 compressing a baseplate against said open side of said housing thereby causing said continuous bead of sealant to flow between (i) said baseplate, (ii) said circuit board, and (iii) said flange. 
 
     
     
       13. The method according to  claim 12 , further comprising the step of:
 curing said sealant to bond said circuit board, said housing and said baseplate together as said electronic control unit. 
 
     
     
       14. The method according to  claim 12 , further comprising the step of:
 assembling a connector and a plurality of compliant pins having a right angle bend to said circuit board to create a subassembly prior to said circuit board being disposed on said shelf, wherein said connector fits into a connector opening in a side of said housing orthogonal to said open side. 
 
     
     
       15. The method according to  claim 14 , wherein an interface between said connector and said housing is free of said sealant. 
     
     
       16. The method according to  claim 12 , wherein said housing is secured to said baseplate solely by said sealant. 
     
     
       17. The method according to  claim 12 , further comprising the step of:
 securing said housing to said baseplate outside of said sealant using one or more fasteners. 
 
     
     
       18. The method according to  claim 12 , further comprising the step of:
 aligning said baseplate to said open side of said housing with said sealant already applied prior to said compression of said baseplate to said housing. 
 
     
     
       19. The method according to  claim 12 , wherein said sealant is cured by at least one of heat curing, humidity curing, ultra-violet light curing, and chemical curing. 
     
     
       20. The method according to  claim 19 , wherein said sealant provides a seal against fluid penetration into an interior of said housing.